Pneumatic-tire protector.



P. T. COFH'ELD. PNEUMATIC TIRE PROTECTOR. APPLICATIVON 21.1.20 JuNE'w, 1915.

Patented Apr. 25, 1916.

PETER T. COFFIELD, OF DAYTON. OHIO.

PNEUMATIC-TIRE PROTECTOR.

Application filed June 16, 1915.

To all TlhOflt it may concern.

Be it known that I, PETER T. Corrmu), a citizen of the United b'tates. residing at Dayton. in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Pneumatic- Tire Protectors; and I do declare the following to be a full, clear. and exact description of the invention. such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to theaccompanying drawings. and to the letters and figures of reference marked thereon. which form a part of this specification.

This invention relates to new and useful improvements in pneumatic tires and has special reference to a firm elastic rubber shield or protector. Experience has demonstrated that innerliners when composed of rubber and a non-elastic fabric or material united in any manner will not conform to the contour bf the outer casing under all conditions. and as a consequence will create friction between the innerliner and the outer casing. This friction necessarilyproduces heat which has a tendency to destroy the fabric of the outer casing and also the non-elastic fabric of the innerliner. This is a serious objection aside from the fact that the union of fabric with rubber in producing an innerliner interferes very materially with the necessary elasticity of the innerliner. So far as I am aware the use of innerliners has been prevented wholly by a construction which combined elastic rubber with a non-elastic material such, for example, as fabric, leather, silk, metal, etc.

It is, therefore, the object of my invention to provide an innerliner constructed wholly of firm elastic rubber of a non-porous character and wholly free from any amalgamation or union with non-elastic material. This innerliner is interposed between the inner tube and the outer casing and affords means for preventing the inner tube from being punctured and the fabric of the outer casing from being damaged or weakened from running over stones or other obstructions which often cause the tread of the easing to be damaged by what is known as stone-bruises. These stone-bruises develop into blow-outs by breaking or weakening the fabric of the outer casing which as well Specification of Letters Patent.

Patented A pr. 25. .1911 ti.

Serial No. 34,388.

known lies adjacent to the innersurfacc of said outer casing.

A further advantage due to my invention lies in the protection it affords to the outer casing from being rim-cut when the inner tube is deflated or collapses by reason of the air therein escaping. In this case the rubber protector. which. as before stated. is free from any connection with fabric or other non-elastic material which would interfere with the elasticity thereof, and is interposed between the inner tube and the outer casing. and is pressed into the space between the flanges of the rim and forms a cushion which acts as a protector to prevent rim-cutting'of the outer casing.

As before stated, my improved protect-or consists of clear rubber. That is to say. rubber that is entirely free from any union with a fabric of any kind or other material that is common in the construction of innerliners heretofore used. It may here be stated, however. that innerliners containing fabric so constructed have the disadvantage of not being sufiiciently elastic at all points so as to conform to all parts of the inner surface of the casing. Owing to this, the fabric, which is usually built up on innerliners', is necessarily of such a rigid character as to cause ruptures of the same. and friction between the so-called innerliner and the casing which results in damage to both.

The object of the present invention is to.

provide a protecting medium in the form of a firm elastic rubber liner unmixed with and disconnected from any non-elastic material, such as fabric, leather, metal, etc., between the inner tube and outer casing and which is devoid of rigidity and is so constructed that a requisite elasticity is present in all parts thereof and which is of such thickness as to prevent the inner tube from being punctured. To these ends my invention consists of an interposed rubber shield or liner which is non-attached to either the outer casing or the inner tube or to anything else but which is held in its effective position by the inflation of the inner tube so that said shield or liner may be removed from tires when the outer casing has been worn out and utilized in other tires. This is due to the fact that it is not necessary to cement or otherwise fasten the protector in position.

Preceding a more detail description of the invention, reference is made to the accompanying drawings of which Figure 1 is a cross-sectional view of a tire having my improved protector in position therein, and Fig. 2 is a similar view of the protector removed from the tire.

It may be stated that my invention is applicable to any form of tire employing any construction of outer casing in connection with an inner or pneumatic tube. In the present case, I have shown a common form of outer casing which is composed of an outer tread portion 1 of firm rubber, as is usually the case, and the inner portion of which is constructed of various layers of fabric 2 combined with rubber and united to the tread in a well known manner. I have also shown an ordinary form of clen'cher rim 3 which holds the casing in position in the usual manner. My invention consists of the rubber protector at which is shown as lying between the inner tube 5 and the fabric 2 of the outer casing. This rubber shield or protector 4 is of a desirable thickness to provide a substantially elastic protection to the inner tube and also a backing for the outer casing to prevent stone-bruises. This rubber protector is held firmly in its position by the inflation of the inner tube and, being devoid of any fabric in its composition, it necessarily avoids any shifting or sliding movement between the protector and the outer casing. Therefore, friction and heat which would be otherwise caused is wholly avoided. Owing to the protector being of uniform elasticity throughout, the defects .and disadvantages of rigidity found in other forms of innerliners that contain fab ric is wholly avoided.

A desirable and advantageous feature of my improved protector is due to the fact that it may be used indefinitely and that its application does not require the use of any form of fastening means, either cement or other, and owing to this it may be applied from one tire to another as desired.

Having described my invention. what 1 claim is,

1. The combination with an outer casing and an inner tube, of a firm and elastic rubber inner-liner interposed between said outer casing and said inner tube and extending partially around the sides of said inner tube. said inner-liner providing an elastic wall between the outer casing and the inner tube which is free from any connection with said outer casing and said inner tube and supports the outer casing when the inner tube is inflated, thereby preventing said outer casing from being stone-bruised or the fabric thereof becoming weakened.

In a tire for vehicle wheels, an innerliner interposed between the inner surface of the outer casing and the outer circumference of the inner tube and confined to the tread portion of the outer casing, said innerliner being constructed offirm and elastic rubber free from any union or connection with fabric, leather, or any material foreign in character to rubber, said inner-liner being free' from any connection with the outer casing or inner tube and providing an elastic wall between the tread portion of the outer casing and the inner tube.

3. In combination with an outer casing or tire and an inner tube, an inner-liner composed of firm and elastic rubber of sufiicient thickness and width to form a backing or support for the outer casing when under pressure from the inflated inner tube, said inner-liner being free or loose from the outer casing and inner tube, whereby it is permitted to adjust itself and to yield with the casing when in use.

In testimony whereof I afiix my signature.

PETER T. COFFIELD.

I Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. G. 

